Nd:YAG laser pulses of 9 nanosecond pulse duration and operating wavelength at 1.06 μm, were utilized to drill high thermal conductivity and high reflectivity aluminum and copper foils. The results showed a dependence of drilled holes characteristics on laser power density and the number of laser pulses used. Drilled depth of 74 ϻm was obtained in aluminum at 11.036×108 W/cm2 of laser power density. Due to its higher melting point, copper required higher laser power density and/or larger number of laser pulses to melt, and a maximum depth of 25 μm was reached at 13.46×108 W/cm2 using single laser pulse.
مفهوم معامل الارتباط كمقياس يربط بين متغيرين هذا يجلب انتباهنا إلى موضوع الإحصاء في كل المستويات. أكثر من ذلك هناك ثلاث نقاط خاصة هي اعتيادياً نشدد عليها كما يأتي:-
(1 معامل الارتباط هو الدليل المعياري والذي قيمته لا تعتمد على قياسات
المتغيرات الأصلية.
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In this study, we compare between the autoregressive approximations (Yule-Walker equations, Least Squares , Least Squares ( forward- backword ) and Burg’s (Geometric and Harmonic ) methods, to determine the optimal approximation to the time series generated from the first - order moving Average non-invertible process, and fractionally - integrated noise process, with several values for d (d=0.15,0.25,0.35,0.45) for different sample sizes (small,median,large)for two processes . We depend on figure of merit function which proposed by author Shibata in 1980, to determine the theoretical optimal order according to min
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The research aimed to know favoured mass media for children and
modifying their behaviour ,the child became aquires the information from
mass media that he exposure them without any guidance , where upon the
quidance proqrammes becomes real danger whereas qet out their civil
style and converting to deadly poisons,and because of little study for this
supject the two researchers opined to perform astudy to know the favoured
mass media to the children and what are the mass media that modify their
behavior according to ther parent points of view ,after propring the research
measurement and the suilable statical methods it has shown that there are
mass media affect in children behavior ,they are st
ABSTRACT
The study aimed to evaluate the information label of some local pickle products and estimate sodium benzoate therein. 85 samples of locally made pickles were collected from Baghdad city markets and randomly from five different areas in Baghdad it included (Al-Shula, Al-Bayaa, Al-Nahrawan, Al-Taji, and Abu Ghraib), which were divided into groups P1, P2, P3, P4 and P5, respectively, according to those areas, samples information label was scanned and compared with the Iraqi standard specification for the information card of packaged and canned food IQS 230, the results showed that 25.9% of the samples were devoid of the indication card informa
... Show MoreThis study was conducted to evaluate the bottled water quality for the six-producing companies in Baghdad city, where selected six brands which are the most marketed in the Iraqi market, especially in Baghdad, where taking the proper amount of bottled water in September 2015 and included the studied characteristics (EC , pH ,TDS, Turbidity, Ca+2, Mg+2, Cl-, No3-, So4-2, HCO3-, Na+ and K+) in addition to the total population of bacteria aerobic and coliform, and compare the results with the standard specifications of the Iraqi and the World Health Organization (WHO), as well as to compare the results of sampling specifications mentioned on the packaging by the producing companies. The results showed the presence of high significant differ
... Show MoreThe experiment was conducted in Baghdad for study effect using mold board and disc plows as main factor , and second factor was three speeds 1.85 , 3.75 and 5.62 km / hr , and sub-second factor was three levels of soil moisture 21,18 and 14 % to determined data fuel consumption and economy costs machine unit in silt clay loam with depth 22cm. The experiment was a split – split plot arrangement in a randomized complete block design with three replications and statistical analysis using Least Significant Design 0.05 was used to compare the means of treatments. Mold board recorded least fuel consumption and cast fixed and variable and management and total costs of tractor and plow costs and total cost. Increasing forward speeds of the t
... Show MoreThis paper deals with the preparation of new monomers and polymers which including heterocyclic unit. The diacid chlorides compounds [1-3] were prepared from the reaction of glutaric acid, adipic acid, terephthalic acid with thionyl chloride. Succinic acid reacted with ethanol to produce compound [4]. Compound [4] reacted with hydrazine hydrate to obtain succinic hydrazide [5].Compound [5] reaction with CS2 and KOH in absolute ethanol to produce compound [6].The polymers [7-12] have been created by reacting diacid chlorides compounds [1-3] with compound[5] or [6] in dry pyridine with some drops of DMF. The topology of produced compounds has characterized through their spectral and analytical data as in FT-IR spectra, Thermal analysis [DSC,
... Show MoreA biconical antenna has been developed for ultra-wideband sensing. A wide impedance bandwidth of around 115% at bandwidth 3.73-14 GHz is achieved which shows that the proposed antenna exhibits a fairly sensitive sensor for microwave medical imaging applications. The sensor and instrumentation is used together with an improved version of delay and sum image reconstruction algorithm on both fatty and glandular breast phantoms. The relatively new imaging set-up provides robust reconstruction of complex permittivity profiles especially in glandular phantoms, producing results that are well matched to the geometries and composition of the tissues. Respectively, the signal-to-clutter and the signal-to-mean ratios of the improved method are consis
... Show MoreIraqi oil crudes have some of the physical and chemical characteristics that distinguish it from other types of oil crudes in the world. Some of these features such us molecular composition, rheological, viscosity and emulsions are studied carefully by researchers. In this work, a comparative study of the linear and the non-linear optical properties for typical heavy and light crude oils of Iraqi origin was studied utilizing Z-scan technique. The He -Ne laser of wavelength 632.8 nm had been used for this purpose. These samples were collected from Basra and Kut oil fields. The values of the non-linear refractive index (n2), non-linear absorption coefficient (β), and third-order electrical susceptibility (χ3) were e
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